Some of the following may be considered weird ways to use a credit card, but if you're willing to get a little outside of your comfort zone, you could earn hundreds of dollars in additional rewards every year. 1. Buy gift cards A lot of rewards credit cards offer bonus rewards on certain purchase categories, but that doesn't mean you can't get more value on spending made outside of those types of purchases. If your card offers a high rewards rate on grocery store purchases, for example, check your local ...